1. Field of the Invention
The present invention relates to an integrated circuit (IC) card, more specifically, to an autonomous IC card which is configured to directly and autonomously communicate with another device connected to an IC card terminal directly or via a network.
2. Description of the Related Art
FIG. 1 is a view for describing a conventional scheme of exchanges of signals between an IC card and an IC card terminal.
Here, the IC card terminal includes an IC card reader/writer 200 and an IC card terminal main body 300. Although an IC card 100 and the IC card reader/writer 200 are schematically illustrated as being separated herein, the IC card 100 and the IC card reader/writer 200 may be configured into a contact less type as described therein, or alternatively, the IC card 100 and the IC card reader/writer 200 may be configured into a contact type in which the IC card 100 is typically inserted into the IC card reader/writer 200.
Upon processing by use of the IC card 100 as described above, the IC card terminal main body 300 serves as a master device and the IC card 100 serves as a slave device. In other words, when an operator intends to execute processing by use of the IC card 100, the operator firstly inputs an instruction to an input terminal (not shown) provided to the IC card terminal main body 300. In response to the instruction, the IC card terminal main body 300 being the master device transmits a command to the IC card 100 via the IC card reader/writer 200. Upon receipt of the command, the IC card 100 being the slave device executes processing corresponding to the command, and returns an execution result to the IC card terminal main body 300 via the IC card reader/writer 200.
FIG. 2 is a view for describing a conventional scheme of exchanges of signals in the case where two IC cards communicate with each other.
In the drawing, an IC card reader/writer 200b is connected to the IC card terminal main body 300 in addition to the configuration shown in FIG. 1. Here, an IC card 100b is connected to the IC card reader/writer 200b either in a contactless mode or in a contact mode.
As similar to the case in FIG. 1, an operator firstly inputs an instruction concerning communication between the IC cards to the input terminal (not shown) provided to the IC card terminal main body 300. In response to the instruction, the IC card terminal main body 300 transmits a command to an IC card 100a via an IC card reader/writer 200a. Upon receipt of the command, the IC card 100a executes processing corresponding to the command, and outputs a response A which is an execution result. The response A outputted from the IC card 100a is inputted to the IC card terminal main body 300 via the IC card reader/writer 200a. The IC card terminal main body 300 performs a relaying operation of information, concerning the response A in this case. The response A outputted from the IC card terminal main body 300 is inputted to the IC card 100b via the IC card reader/writer 200b. The IC card 100b executes processing corresponding to the inputted response A, and outputs a response B which is an execution result. The response B outputted from the IC card 100b is inputted to the IC card terminal main body 300 via the IC card reader/writer 200b. The IC card terminal main body 300 performs a relaying operation of information, concerning the response B in this case. The response B outputted from the IC card terminal main body 300 is inputted to the IC card 100a via the IC card reader/writer 200a. 
The operations are basically the same when the above-described exchanges between the IC card 100a and the IC card 100b continue. In other words, the IC card terminal main body 300 always plays a role to perform relaying operations of information exchanged between the IC card 100a and the IC card 100b. 
Incidentally, in conventional communication between IC cards, the IC card terminal main body always plays the role to perform relaying operations of information concerning the communication between the IC cards as described above. Therefore, conventionally, an intermediate device as represented by the IC card terminal main body has been capable of falsification or theft of the information communicated between the IC cards. Hence there has been conventionally a problem that communication of accurate information between the IC cards is not ensured.